Modified Method for Estimation of Total Risk Factor (TRF) for Selected Dams in Iraq

The main objective of the present study is to determine the risk class of Haditha and Hemrin Dams The weighting points for various risk factors of the selected dams were substituted in Eq. (5) to find the TRF of each dam. For the studied dams, the data related to various risk factors was collected from the State Commission of Dams and Reservoirs (SCODR), Iraq. The studied dams are outside the seismic zone, and flood is considered the main hazard that makes the dams vulnerable to overtopping. Three scenarios that considered different water levels in Haditha and Hemerin Dams reservoirs were analyzed. In the worst scenario, the water levels in the reservoirs of both dams were taken more than the flood control level (152.2 m.a.s.l in the reservoir of Haditha Dam and 107.5 m.a.s.l in the reservoir of Hemrin Dam). The calculated TRFs for the worst scenario were 168 and 216 for Haditha Dam and Hemrin Dam, respectively. The rating for both TRFs showed that the risk category is high (class Ill). The modified method is a simplified method dam engineers use to easily classify a dam's total risk.